cyclopropyl1.gif
cyclopropyl1.gif

Place syntheses below

external image moz-screenshot-7.pngCyclopropyl1.JPG


1) Formation of the lithium enolate
2) aldol condensation
3) reduction
4) halogenation via Tosyl Ester intermediate
5) SN2 via sodium methoxide
6) cyclopropane ring formation via Zinc Coupled catalyst

The use of lithium di-isopropyl amide prevents the acetone from adding to the ethaldehyde.

Sources:

Winter, Arthur. Organic Chemistry I for Dummies. Indianapolis: Wiley.
Hathaway, Bruce A. Organic Chemistry: The Easy Way. Hauppauge: Barron's Educational Series, 2005.
Bloch, Daniel R. Organic Chemistry Demystified. McGraw-Hill Companies, 2005.
Wade pgs 353-355, 232-242, 272, 316-317, 376-377

Sean and Jesson
I like your use of the Aldol condensation. This type of reaction is central to synthesis of complicated molecules and to biosynthesis. (of course, not with LDA in the latter). You dont need to make the bromide in step 4. The toscylate will be a fine leaing group for the Williamson ether synthesis in step 5.
The only thing that you need to add is the reterosynthesis.
Bruce Bondurant




Retrosynthesis




  1. Simmons-Smith reaction for the formation of cyclopropane
  2. SN2 substitution
  3. Formation of an ether via Williamson ether synthesis. Ethers can be formed by nucleophilic reactions with alkyl halides or alkoxides (Wade pg. 497-499).
  4. Use of NaBH4 to oxidize alcohol to aldehyde
  5. aldol condensation (Wade pg. 1058)
  6. Formation of Lithium enolate
  7. Starting material of less than 3 carbons

nice!
Bruce Bondurant